In recent years polymers referred to as dense star polymers or starburst polymers have been developed. It has been found that the size, shape and properties of these dense star polymers or starburst polymers can be molecularly tailored to meet specialized end uses. Starburst polymers have significant advantages which can provide a means for the delivery of high concentrations of carried material per unit of polymer, controlled delivery, targeted delivery and/or multiple species delivery or use.